A telecommunications system will typically include one or more control stations (which will be referred to hereafter as central stations or central terminals) at which equipment is contained for managing the telecommunications network. In a wired telecommunications system, this equipment may be at one or more of the telephone exchange sites in the telecommunications system. In a wireless telecommunications system, a central station may be included that is connected to the public telephone network and exists to relay messages from subscribers in the cell controlled by the central station to the public telephone network, and vice versa. Typically, a site controller, or server, is connectable to the central station for controlling the central station. However, this arrangement has generally required an operator to be physically present at the site controller in order to manage the central terminal. UK Patent application 9603782.5, filed Feb. 22, 1996, alleviates this problem by providing a server that is local to the central station and has an object model maintained thereon identifying the structure of the central station, and then enabling a number of client stations, either local or remote, to connect to the local server in order to invoke operations to alter the object model on that server. Such alterations are then passed by the local server on to the central station to cause corresponding changes in the central station.
However, in such an arrangement as described in UK Patent application 9603782.5, the client station is required to contain a complete copy of the object model maintained in the server. This complete copy of the object model would typically be made at the time that the client station first connects to the server. However as telecommunications systems become more complex, so the object model maintained on the server becomes more complex, and the time taken to make a complete copy of that object model on the client station becomes progressively longer. Hence there is a significant initial performance degradation associated with establishing the copy of the object model on the client station. Further, it is possible that the client station will be used to manage the object models on a number of server stations. Hence, if a complete copy of each object model is to be stored at the client station, then a large amount of memory is required at the client station.
To alleviate this problem, it is proposed that only a portion of the object model maintained on the server station be copied to the client station when the client station initially connects to the server. This alleviates the initial performance problem resulting from loading the entire object model from the server, and also reduces the memory requirements of the client station. However, it will be apparent to those skilled in the art that this approach does raise some additional issues. The portion of the object model loaded on the client station may not always provide the required level of detail about the telecommunications system to enable the user of the client station to effectively manage the telecommunications system. Additionally, since the former client-server arrangement described in UK patent application no 9603782.5, filed Feb. 22, 1996, operates on the principle that the client will always have a complete copy of the object model on the server, the client station will receive commands from the server reflecting updates made to various objects of the object model. The portion of the object model may not contain the objects in question, and so the client station may be unable to alter its copy of the model to reflect these changes.